Forgot to add core_ext/string/starts_ends_with.rb

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@2176 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

activesupport/lib/active_support/core_ext/string/starts_ends_with.rb

@@ -0,0 +1,20 @@
+module ActiveSupport #:nodoc:
+  module CoreExtensions #:nodoc:
+    module String #:nodoc:
+      # Additional string tests.
+      module StartsEndsWith
+        # Does the string start with the specified +prefix+?
+        def starts_with?(prefix)
+          prefix = prefix.to_s
+          self[0, prefix.length] == prefix
+        end
+
+        # Does the string end with the specified +suffix+?
+        def ends_with?(suffix)
+          suffix = suffix.to_s
+          self[-suffix.length, suffix.length] == suffix      
+        end
+      end
+    end
+  end
+end